This invention relates to diagnosis of electrical and mechanical faults in a bi-stable magnetically latching solenoid.
Mechanically actuated switches have been utilized to detect solenoid plunger motion through mechanical coupling thereto. These have proven to be somewhat unreliable due to various mechanical failure modes and tolerance stack. Additionally, mechanical detection adds expense, piece count and packaging requirements to any system utilizing such a solenoid actuation detector.
Additionally, non-actuation of a solenoid plunger may be due to electrical or mechanical faults. Mechanically actuated switches are incapable of diagnosis beyond simplistic traditional go/no go applications and cannot be used to distinguish between mechanical and electrical faults.
Therefore, it is desirable to provide for solenoid diagnosis of electrical and mechanical faults without the additional burdens and shortcomings of mechanical systems.